TY - JOUR
T1 - Neil2-null mice accumulate oxidized DNA bases in the transcriptionally active sequences of the genome and are susceptible to innate inflammation
AU - Chakraborty, Anirban
AU - Wakamiya, Maki
AU - Venkova-Canova, Tatiana
AU - Pandita, Raj K.
AU - Aguilera-Aguirre, Leopoldo
AU - Sarker, Altaf H.
AU - Singh, Dharmendra Kumar
AU - Hosoki, Koa
AU - Wood, Thomas G.
AU - Sharma, Gulshan
AU - Cardenas, Victor
AU - Sarkar, Partha S.
AU - Sur, Sanjiv
AU - Pandita, Tej K.
AU - Boldogh, Istvan
AU - Hazra, Tapas K.
N1 - Publisher Copyright:
© 2015 by The American Society for Biochemistry and Molecular Biology, Inc. Published in the U.S.A.
PY - 2015/10/9
Y1 - 2015/10/9
N2 - Why mammalian cells possess multiple DNA glycosylases (DGs) with overlapping substrate ranges for repairing oxidatively damaged bases via the base excision repair (BER) pathway is a long-standing question. To determine the biological role of these DGs, null animal models have been generated. Here, we report the generation and characterization of mice lacking Neil2 (Nei-like 2). As in mice deficient in each of the other four oxidized base-specific DGs (OGG1, NTH1, NEIL1, and NEIL3), Neil2-null mice show no overt phenotype. However, middleaged to old Neil2-null mice show the accumulation of oxidative genomic damage, mostly in the transcribed regions. Immunopulldown analysis from wild-type (WT) mouse tissue showed the association of NEIL2 with RNA polymerase II, along with Cockayne syndrome group B protein, TFIIH, and other BER proteins. Chromatin immunoprecipitation analysis from mouse tissue showed co-occupancy of NEIL2 and RNA polymerase II only on the transcribed genes, consistent with our earlier in vitro findings on NEIL2's role in transcription-coupled BER. This study provides the first in vivo evidence of genomic region-specific repair in mammals. Furthermore, telomere loss and genomic instability were observed at a higher frequency in embryonic fibroblasts from Neil2-null mice than from the WT. Moreover, Neil2-null mice are much more responsive to inflammatory agents than WT mice. Taken together, our results underscore the importance of NEIL2 in protecting mammals from the development of various pathologies that are linked to genomic instability and/or inflammation. NEIL2 is thus likely to play an important role in long term genomic maintenance, particularly in long-lived mammals such as humans.
AB - Why mammalian cells possess multiple DNA glycosylases (DGs) with overlapping substrate ranges for repairing oxidatively damaged bases via the base excision repair (BER) pathway is a long-standing question. To determine the biological role of these DGs, null animal models have been generated. Here, we report the generation and characterization of mice lacking Neil2 (Nei-like 2). As in mice deficient in each of the other four oxidized base-specific DGs (OGG1, NTH1, NEIL1, and NEIL3), Neil2-null mice show no overt phenotype. However, middleaged to old Neil2-null mice show the accumulation of oxidative genomic damage, mostly in the transcribed regions. Immunopulldown analysis from wild-type (WT) mouse tissue showed the association of NEIL2 with RNA polymerase II, along with Cockayne syndrome group B protein, TFIIH, and other BER proteins. Chromatin immunoprecipitation analysis from mouse tissue showed co-occupancy of NEIL2 and RNA polymerase II only on the transcribed genes, consistent with our earlier in vitro findings on NEIL2's role in transcription-coupled BER. This study provides the first in vivo evidence of genomic region-specific repair in mammals. Furthermore, telomere loss and genomic instability were observed at a higher frequency in embryonic fibroblasts from Neil2-null mice than from the WT. Moreover, Neil2-null mice are much more responsive to inflammatory agents than WT mice. Taken together, our results underscore the importance of NEIL2 in protecting mammals from the development of various pathologies that are linked to genomic instability and/or inflammation. NEIL2 is thus likely to play an important role in long term genomic maintenance, particularly in long-lived mammals such as humans.
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U2 - 10.1074/jbc.M115.658146
DO - 10.1074/jbc.M115.658146
M3 - Article
C2 - 26245904
AN - SCOPUS:84943800916
SN - 0021-9258
VL - 290
SP - 24636
EP - 24648
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 41
ER -